The combination lock and valve herein illustrated is designed to enable the operator to determine the correct positioning of the valve actuator to effect opening and closing once the combination is known by the audible clicking of detents provided for this purpose, which detents also determine the open and closed positions of the valve parts, to stymie manipulation by an unauthorized operator to open the valve in the absence of knowing the proper combination and to simplify manufacture and installation. The audible clicking provides the advantage that the device may be manipulated without having to match indicia on a pointer or dial and so can be manipulated in uncertain light or darkness without the aid of a flashlight.